What are specific things to focus on while running and drills or exercises to do to improve my form and make it more efficient? I’d like to think my form is pretty decent but there’s room for improvement of course.

What are specific things to focus on while running and drills or exercises to do to improve my form and make it more efficient? I’d like to think my form is pretty decent but there’s room for improvement of course.

Run up hills. A lot.

You will notice a guitarist doesn't become more efficient by playing the trombone.